However, the last step which says to change the CHMOD of a folder, I got an error saying that the directory does not exist.

Open Office now appears in my Ubuntu start menu, but clicking on it does nothing. I tried a reboot.

Below is what I could copy from my terminal.

I am running the latest Ubuntu. I have not uninstalled Libreoffice as suggested somewhere. The reason is that in the Ubuntu software centre, Libre office appears to be made up of several components and I don't know which ones to remove (or all maybe?). They are Libreoffice Draw, Math, Writer, Calc.

You don't need Open Office. The differences between LibreOffice and Open Office are minimal to say the least and given that the dynamic of the community is now with LibreOffice which comes nicely pre-installed in Ubuntu, I wouldn't waste your time with OpenOffice.

Oracle decided after acquiring Sun that it was not interested in maintaining it and offloaded it to the Apache Foundation. Meanwhile many of the developers started LibreOffice as a fork of OpenOffice. Some developers do nevertheless continue to work on OpenOffice and I believe there was a new release not so long ago but as I said the differences between the two are negligible and the dynamic is clearly with LibreOffice these days.

Regarding uninstalling LibreOffice, I think you'll need to uninstall the packages separately since the meta-package is not installed by default.

Then I'd remove any OpenOffice packages - use synaptic - and start again using the method you were given.

However, once again I cannot recommend to go to all that fuss for a near identical suite of apps to what you have comfortably installed already.